Call DidAttachLocalMainFrame in PrintRenderFrameHelper

Add missing calls to WebView::DidAttachLocalMainFrame() after setting up
the local main frame for a given web view.

Bug: 1053546
Change-Id: If74dcc23b91dd5218c526d48a6b49b84d4b809dc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2102571
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#750305}

components/printing/renderer/print_render_frame_helper.cc

@@ -701,6 +701,7 @@ void PrintRenderFrameHelper::PrintHeaderAndFooter(
 
   blink::WebWidgetClient web_widget_client;
   blink::WebFrameWidget::CreateForMainFrame(&web_widget_client, frame);
+  web_view->DidAttachLocalMainFrame();
 
   base::Value html(
       ui::ResourceBundle::GetSharedInstance().LoadDataResourceString(
@@ -938,6 +939,7 @@ void PrepareFrameAndViewForPrint::CopySelection(
       blink::WebLocalFrame::CreateMainFrame(web_view, this, nullptr, nullptr);
   frame_.Reset(main_frame);
   blink::WebFrameWidget::CreateForMainFrame(this, main_frame);
+  web_view->DidAttachLocalMainFrame();
   node_to_print_.Reset();
 
   owns_web_view_ = true;